PI = 3.1415926


def circle(r):
    global PI
    s = r * r * PI
    c = 2 * r * PI
    return format(c, '.2f'), format(s, '.2f')


def main():
    r = float(input("请输入圆的半径\n"))
    print("圆的周长与面积为", circle(r))


main()
